耳膜激振式人工中耳压电作动器设计与实验

Design and Experiment of Eardrum Stimulating Middle Ear Implant Piezoelectric Actuator

针对现有耳膜激振式人工中耳的作动器存在不能适应患者个体耳道尺寸差异、高频增益不足、受电磁干扰的问题,设计了一种新型悬浮式压电作动器。首先,结合人耳解剖结构,对作动器的机械结构及宏观尺寸进行了初步设计;其次,针对压电叠堆存在输出位移不足的问题,引入了位移放大器,并采用粒子群优化算法对其位移放大倍数进行了优化;随后,构建了压电作动器-人耳耦合力学模型,分析了金属壳体的质量和压电叠堆的层数对作动器听损补偿性能的影响,并确定了最佳的设计参数;最后,基于优化的参数制造出作动器样机,并对其听力补偿性能进行了测试。结果表明,该作动器具有工作频带宽(0.2 kHz~10 kHz)、谐波失真低(THD≤2%)、高频性能优越的优点。该作动器适用于耳膜激振的听损补偿,为听力损失的临床治疗提供了新的解决方案。

A novel suspended piezoelectric actuator has been designed to address issues associated with existing eardrum stimulation middle ear implants,including challenges with accommodating individual variations in ear canal dimensions,insufficient high-frequency gain,and susceptibility to electromagnetic interference.Initially,considering the anatomical structure of the human ear,the mechanical structure and macroscopic dimensions of the actuator are preliminarily designed.Subsequently,to address the issue of inadequate output displacement in the piezoelectric stacks,a displacement amplifier is introduced,and its amplification factor is optimized using a particle swarm optimization algorithm.Following this,a coupled mechanical model of the piezoelectric actuator and the human ear is established to analyze the impact of the mass of the metal shell and the number of layers in the piezoelectric stack on the hearing loss compensation performance of the actuator.The optimal design parameters are determined through this analysis.Finally,a prototype of the actuator is manufactured based on the optimized parameters,and its hearing compensation performance is tested.The results indicate that the actuator possesses a broad operating frequency range(0.2 kHz~10 kHz),low harmonic distortion(THD≤2%)and superior high-frequency performance.This actuator is suitable for compensating hearing loss in eardrum stimulation,offering a new solution for the clinical treatment of hearing impairment.